Hydraulic vehicle brake system with an anti-skid system

Claim 1

A hydraulic vehicle brake system having a dual-circuit main brake cylinder, a reservoir for the main brake cylinder, first and second brake circuits for wheel brakes of a motor vehicle, an anti-skid system associated with the wheel brakes that has brake pressure modulation valve arrangements and a recirculating pump (13, 14) for each brake circuit, an automatic braking system in cooperation with the anti-skid system, at least one 2/2-way valve (324, 328, 357) for each brake circuit between said dual circuit main brake cylinder, the reservoir and the anti-skid system, said at least one 2/2-way valve for each brake circuit is connected with said brake cylinder and reservoir and, connected to the anti-skid system, an integral cylinder (301): a uniform diameter cylinder bore in said integral cylinder a separating piston displaceably disposed in said cylinder bore for each brake circuit, said separating pistons separate a secondary chamber from a primary chamber in said cylinder bore, said integral cylinder includes a separating piston restoring spring for each piston, and said automatic braking system includes a common auxiliary pump (49) for both brake circuits, wherein during automatic brake operation the auxiliary pump supplies pressure to displace the separating pistons and close the 2/2-way valves (324, 328, 357), and a control device for controlling the anti-skid system to avoid a danger of wheel locking, and the automatic braking system for automatic braking, the cylinder bores of the two separating pistons (314, 315; 345, 346) are oriented on the same axis, and embodied as a blind bore (303; 344) and accommodated in a common integral cylinder (301; 341); that an end opening (304; 344), of the blind bore (302; 342) is sealed with a lid (305); that both separating pistons (314, 315; 345, 346) are disposed oriented toward each other with their primary-side ends (316; 349, 350) between separating piston restoring springs (317, 318); and that an auxiliary pressure connection (313) is disposed in the integral cylinder (301; 341), which discharges between the separating pistons, and is supplied from said auxiliary pump (49).